The present invention relates to a camera of the type wherein the functions of film-winding, film-rewinding and other mechanisms are driven by a single motor.
In a recent small-sized camera especially in a compact type camera, an automation of camera functions and operations has been promoted following the automation of exposure and focusing and at the present time there are offered cameras having therein a small but highly efficient motor that performs automatically the operations of film-winding, film-rewinding and shutter-setting through only the switch operation.
As a structure of a driving system in these cameras, a changeover both of the rotating direction of a motor and a simple clutch mechanism causes a camera to perform aforesaid film-winding, film-rewinding and shutter-setting operations, accordingly, when an independent function should be added to the camera, the mechanisms for power transmission and switch-over for aforesaid additional function should be provided separately, which has caused disadvantages that the structure and operations of a camera are complicated.
For the materialization of a camera wherein an operation such as a changing operation of a focal length that is completely different from film-winding and film-rewinding operation should also be performed by one motor, there is desired a novel power transmission device which is simple in structure and is efficient with a little loss of power and further is easy to operate without an erroneous operation.
Furthermore, when the lens shifting necessary for aforesaid changing of a focal length is added to a camera as a camera action other than film transportation and when the lens shifting is intended to be performed by aforesaid motor, one part of aforesaid driving system should be separately used in two systems. Therefore, the changeover operation of the driving mechanism for the foregoing is necessary and the control circuit for controlling rotation time of the motor for the aforesaid changeover operation is concurrently needed to be switched.
For the switching of the control circuit, it may be considered that an exclusive switch is provided for each of film transportation and lens shifting and thereby the switching of the control circuit is performed by actuating either one of aforesaid exclusive switches. However, because of two operating switches provided, erroneous operation tends to take place and the controlling device tends to be bulky and expensive partly because of the increase in the number of inputs, which results in the cost increase of a camera.
The present invention, after the solution of aforesaid problems and the improvement, is to provide a camera wherein a film-rewinding operation or an operation of changing a focal length can be conducted from the state of film-winding only by operating either one of film-rewinding member and the operating member for changing a focal length through controlling the motor rotation in one direction into two driving systems by means of a comparatively small-sized controlling device that is free from a fear of an erroneous operation.